LXR linux/arch/x86/kernel/cpu/mcheck/p5.c

   1/*
   2 * P5 specific Machine Check Exception Reporting
   3 * (C) Copyright 2002 Alan Cox <alan@lxorguk.ukuu.org.uk>
   4 */
   5#include <linux/interrupt.h>
   6#include <linux/kernel.h>
   7#include <linux/types.h>
   8#include <linux/init.h>
   9#include <linux/smp.h>
  10
  11#include <asm/processor.h>
  12#include <asm/system.h>
  13#include <asm/mce.h>
  14#include <asm/msr.h>
  15
  16/* By default disabled */
  17int mce_p5_enabled __read_mostly;
  18
  19/* Machine check handler for Pentium class Intel CPUs: */
  20static void pentium_machine_check(struct pt_regs *regs, long error_code)
  21{
  22        u32 loaddr, hi, lotype;
  23
  24        rdmsr(MSR_IA32_P5_MC_ADDR, loaddr, hi);
  25        rdmsr(MSR_IA32_P5_MC_TYPE, lotype, hi);
  26
  27        printk(KERN_EMERG
  28                "CPU#%d: Machine Check Exception:  0x%8X (type 0x%8X).\n",
  29                smp_processor_id(), loaddr, lotype);
  30
  31        if (lotype & (1<<5)) {
  32                printk(KERN_EMERG
  33                        "CPU#%d: Possible thermal failure (CPU on fire ?).\n",
  34                        smp_processor_id());
  35        }
  36
  37        add_taint(TAINT_MACHINE_CHECK);
  38}
  39
  40/* Set up machine check reporting for processors with Intel style MCE: */
  41void intel_p5_mcheck_init(struct cpuinfo_x86 *c)
  42{
  43        u32 l, h;
  44
  45        /* Default P5 to off as its often misconnected: */
  46        if (!mce_p5_enabled)
  47                return;
  48
  49        /* Check for MCE support: */
  50        if (!cpu_has(c, X86_FEATURE_MCE))
  51                return;
  52
  53        machine_check_vector = pentium_machine_check;
  54        /* Make sure the vector pointer is visible before we enable MCEs: */
  55        wmb();
  56
  57        /* Read registers before enabling: */
  58        rdmsr(MSR_IA32_P5_MC_ADDR, l, h);
  59        rdmsr(MSR_IA32_P5_MC_TYPE, l, h);
  60        printk(KERN_INFO
  61               "Intel old style machine check architecture supported.\n");
  62
  63        /* Enable MCE: */
  64        set_in_cr4(X86_CR4_MCE);
  65        printk(KERN_INFO
  66               "Intel old style machine check reporting enabled on CPU#%d.\n",
  67               smp_processor_id());
  68}
  69